Pinch-off of bubbles in a polymer solution

The formation of gas bubbles in a liquid occurs various engineering processes, such as during foam generation or agitation and mixing bubbly flows. A challenge describing the initial bubble is due to singular behavior at pinch-off. Past experiments Newtonian fluids have shown that minimum neck radius follows power-law evolution shortly before break-up. exponent depends on viscosity surrounding liquid, ranges from 0.5 for low 1 large viscosity. However, viscoelastic polymer solution remains unclear, particular, if still captured by how varies with concentration. In this study, we use high-speed imaging analyze pinch-off solutions polymers. We characterize time when varying concentration thus characteristic relaxation chains, describe influence viscoelasticity Our results reveal presence polymers does not thinning until latter stages, their sufficient delays